The banks of navigable artificial or natural flowing or standing water bodies, such as rivers, canals, and also dams, retention basins, outlet troughs (spillways), etc., must generally be protected from erosion, for which rock revetments with or without clamps, or compound rock revetments are generally used.
When canals are to be built, or waterways are to be widened and/or deepened to accommodate larger ships, banks are, as a rule, excavated. This has the disadvantage that not only does substantial quantities of earth on the bank have to be dug up, but also that the deposition of this earth mass in the proximity of the site, in order to hold down costs, is often not possible. Above all, the work expenditure is large, because of the substantial quantities of earth that have to be moved to ensure a natural angle of repose.
To achieve steeper banks with significantly less earth removal, sheet pilings are often erected on the bank. Apart from the fact that the sheet pilings are cumbersome and expensive, they are also foreign features in the environment. People have, therefore, attempted to hide the sheet pilings by introducing swimming and vegetative fascines, which improve the appearance, but results in added expense.
It is therefore desirable to provide a new and improved revetment, a revetment system and a method to protect banks wherein these well known, cumbersome methods of bank widening can be avoided, and the task of creating widened and stable bank zones is achieved by simple, more natural means, without over-designing and expensive work investment.